Transferable Electrode Tip for Resistance Welding Anode Tabs
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing resistance welding techniques face challenges in creating robust and consistent welds between dissimilar materials like nickel anode current collector tabs and stainless-steel casings, often resulting in sticking issues and damage during the welding process, especially when multiple tabs are stacked and welded.
Innovation Solution
A transferable electrode tip with high resistance is introduced between the welding electrode and the anode tabs, concentrating heat for point-welds and ensuring redundancy by making at least two point-welds between the tabs and the casing, which helps in maintaining the weld integrity and preventing material contamination.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If copper welding electrodes are used for resistance welding nickel anode tabs to stainless-steel casings, then the welding process is simple and effective, but the copper electrode sticks to the nickel tab causing contamination and potential tab damage
Solution Approach 1:
A nickel coating is applied to the copper welding electrode, creating an intermediate layer between the copper electrode and nickel anode tab. This nickel intermediary layer prevents direct copper-nickel contact that causes sticking, while still enabling effective resistance welding. The nickel coating acts as a sacrificial barrier that maintains weld integrity without causing contamination.
2Strength
If the anode tab thickness is increased to prevent tearing during electrode withdrawal, then tab strength improves, but the overall cell design becomes more complex and material usage increases
Solution Approach 1:
A thin, sacrificial nickel coating is applied to the welding electrode that is consumed during the welding process. This disposable protective layer prevents damage to the main anode tab structure, allowing thin tabs to be welded without fear of tearing. The nickel coating is sacrificed to protect the more valuable anode tab material.
3Reliability
If multiple anode tabs are stacked and welded together, then electrical connection redundancy improves, but weld consistency and robustness become difficult to achieve
Solution Approach 1:
The nickel coating on the welding electrode changes the electrical resistance parameters at the weld interface, creating more uniform heat distribution across multiple stacked tabs. This parameter modification ensures consistent welding across varying tab configurations, maintaining weld quality whether welding single or multiple tabs together.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach results in robust and consistent welds between the anode tabs and the cell casing, reducing the risk of tab damage and contamination, and ensures reliable connections even when multiple tabs are stacked, enhancing the process capability without adding product functionality.
Implementation Method 1
The transferable electrode tip creates a resistive balance between the ball and case that helps to direct or concentrate the heat generated during the welding process
Implementation Method 2
resistance welding is commonly used... the resistivity of copper is significantly lower than that of the anode current collector materials
Data Source
AI summary
A new weld configuration is used to obtain a robust and consistent resistance weld between the tabs of an anode current collector and the casing of an electrochemical cell. This is done by adding a resistive transferable electrode tip between at least one of the welding electrodes, preferably the movable welding electrode, and the stacked parts that are being joined together. The purpose of the transferable electrode tip is to generate a sufficient amount of heat during the welding process so that the stacked parts are joined together without adding any product functionality. In one embodiment of the present invention, the transferrable electrode tip is a stainless-steel ball, the stacked anode current collector tabs are of nickel, and the cell casing is of stainless-steel.